The present invention pertains to a lightweight hollow core structural building element which can be used as a beam or can be joined with other elements to form a floor, deck or wall panel.
The potential for the use of hollow core elements in the construction of buildings and other structures has been known for many years. Hollow cores of corrugated or honeycomb paper or metal sheet material, enclosed by upper and lower skin panels or sheets, have long been used or proposed for use as floor, wall and roof panels for buildings. However, the use of such hollow core panels has been inhibited because of difficulties in fabricating the panels in an efficient and cost effective manner.
It is known in the prior art to construct building floors or decks with structures that are reinforced and oriented such that loads are distributed in orthogonal directions (e.g. in the direction of main supporting beams and perpendicular thereto). In one such type of construction, as applied to a flat roof structure, parallel main support beams are tied together with bar joist trusses which help distribute the load in directions perpendicular to the beams.
In another type of construction, a concrete floor slab has steel reinforcing running in two directions that are perpendicular to one another, again in an attempt to more evenly distribute the load in both directions. Concrete is eliminated in recessed portions bounded by the steel reinforcing in a sort of inverted egg carton construction.
In both of the foregoing modes of construction, larger spans are attainable by virtue of the orthogonal load distribution. However, both of the foregoing floor plate constructions utilize large amounts of expensive steel and/or relatively massive amounts of concrete.
In my co-pending patent application Ser. Nos. 11/476,474, entitled “Method and Apparatus for Manufacturing Open Core Elements from Web Material”, filed Jun. 28, 2006, and 11/769,879, entitled “Method and Apparatus for Manufacturing Open Core Elements from Web Material”, filed Jun. 28, 2007, which application are incorporated by reference herein, there is disclosed a system for manufacturing hollow core panels of widely varying dimensions using corrugating techniques and a unique lay-up process.